# Mutex and AutoLock are not member of CV cpp
**URL:** https://forum.opencv.org/t/mutex-and-autolock-are-not-member-of-cv-cpp/17186
**Category:** C++
**Tags:** build
**Created:** [April 7, 2024, 5:39am UTC](https://forum.opencv.org/t/mutex-and-autolock-are-not-member-of-cv-cpp/17186 "2024-04-07T05:39:12Z")
**Posts on this page:** 4
**Page:** 1
### Author:  [@nana](https://forum.opencv.org/u/nana)
#### Post date: [April 7, 2024, 5:39am UTC](https://forum.opencv.org/t/mutex-and-autolock-are-not-member-of-cv-cpp/17186/1 "2024-04-07T05:39:12Z")
I am trying to add opencv-4.9.0 to my c++ dll project on windows (visual studio) but when I get these errors:
`Mutex and AutoLock are not member of CV' `AutoLock and AutoLock are not member of CV’
this is coming from heap.h file.
Any ideas?
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### Author:  [@berak](https://forum.opencv.org/u/berak)
#### Post date: [April 7, 2024, 6:09am UTC](https://forum.opencv.org/t/mutex-and-autolock-are-not-member-of-cv-cpp/17186/2 "2024-04-07T06:09:28Z")
> [@nana](#):
>
> Mutex and AutoLock are not member of CV
the _exact, complete_ error msg, please ?
> [@nana](#):
>
> I am trying to add opencv-4.9.0 to my c++ dll project
what _exactly_ are you doing ? what did you install ? how ? from where ?
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### Author:  [@nana](https://forum.opencv.org/u/nana)
#### Post date: [April 7, 2024, 6:57am UTC](https://forum.opencv.org/t/mutex-and-autolock-are-not-member-of-cv-cpp/17186/3 "2024-04-07T06:57:46Z")
I missed some includes, this issue is solved. tnx
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### Author:  [@Hollywise](https://forum.opencv.org/u/Hollywise)
#### Post date: [April 17, 2025, 5:38pm UTC](https://forum.opencv.org/t/mutex-and-autolock-are-not-member-of-cv-cpp/17186/4 "2025-04-17T17:38:16Z")
Hello, I have the exact same issue. I have included opencv to the project and can’t find why they are still missing